About María de Mendoza Díaz de Haro, VI Señora de Mendoza

Her identity as María, heiress of Mendoza may be a mistake. Salazar y Castro thought María, wife of Juan «el Barbudo» Hurtado de Mendoza was daughter of Lope Díaz de Mendoza and María Díaz de Haro (Salazar y Castro, 567).

What is known is that an unnamed daughter of Lope de Mendoza and Maria Diaz married a Juan Hurtado de Mendoza, but his identity is unknown.

MedLands says:

LOPE de Mendoza . m as her third husband, MARÍA Diaz, widow firstly of NUÑO Díaz de Castañeda, secondly of ALFONSO Sánchez de Castilla, daughter of DIEGO López de Haro [Vizcaya] & his wife Teresa Álvarez de Lara. The Nobiliario of Pedro Conde de Barcelos names "D. Maria Diaz" as daughter of "D. Diego Lopez de Salcedo" and his wife "D. Teresa Alvarez, hija de Alvaro Fernandez Potestade", recording in an earlier passage that "D. Alonso Sanchez" married "D. Maria Diaz de Salzedo", in another passage that "Lope o Loy de Mendoça" married "D. Maria Diaz", and in a fourth passage that "Nuno o Maño Diaz de Castañeda" married "D. Maria Diaz" (adding that the couple was childless)[2026]. Lope & his wife had one child:

a) --- . The Nobiliario of Pedro Conde de Barcelos names "D. N." as daughter of "Lope o Loy de Mendoça" and his wife "D. Maria Diaz", adding that she married "D. Juan Hurtado de Mendoça"[2027]. m JUAN Hurtado de Mendoza, son of ---.